I have a pro built 383 flat tappet hydraulic cam in my 36 Chevy street rod w/roller rockers (dynoed @ 455 HP, 468 FtLbs). Yes, I use a zinc additive. It is a little noisy when cold but quiets down when warm. My 2016 SS Camaro with the LT 1 also has roller rockers and they are slightly noisy. My...